Ibha yezimpahla, eyaziwa nangokuthi ibha yomthwalo noma isikhiya somthwalo wezimpahla, iyithuluzi elibalulekile emkhakheni wezokuthutha kanye nokuhlelwa kwempahla.Inhloso yayo eyinhloko ukuvikela kanye nokusimamisa impahla ngaphakathi kwamaloli, ama-trailer, noma iziqukathi zokuthutha ngesikhathi sokuthutha.Le migoqo iyalungiseka futhi ngokuvamile inweba ivundlile phakathi kwezindonga zesikhala sempahla, idale umgoqo ovimbela izimpahla ukuthi zingagudluki, ziwe, noma zonakaliswe ngesikhathi sokuthutha.Amabha wezimpahla abalulekile ekugcineni ubuqotho bokuthunyelwa, ukuqinisekisa ukulethwa kwezimpahla okuphephile nokusebenza kahle, kanye nokunciphisa ubungozi bokulimala noma ukulahleka ngesikhathi sokuthutha.Ngokuguquguquka kwazo kanye nokusebenziseka kalula, amabha wezimpahla adlala indima ebalulekile ekwandiseni ukuhleleka kwezimboni ezahlukahlukene, okunikela ekuphepheni kukonke kanye nokwethenjwa kwenqubo yezokuthutha.